Temperature management system for autonomous vehicles

ABSTRACT

Techniques are described for managing temperature in an autonomous vehicle. An exemplary method comprises performing autonomous driving operations that operate the autonomous vehicle in an autonomous mode, receiving one or more messages from a temperature sensor associated with an electrical device located on or in the autonomous vehicle while the autonomous vehicle is operated in the autonomous mode, determining a cooling technique to reduce the temperature of electrical device, and performing the cooling technique.

TECHNICAL FIELD

This document relates to systems, apparatus, and methods to managetemperature of one or more devices operating on or in an autonomousvehicle.

BACKGROUND

Autonomous vehicle navigation is a technology that can allow a vehicleto sense the position and movement of vehicles around an autonomousvehicle and, based on the sensing, control the autonomous vehicle tosafely navigate towards a destination. An autonomous vehicle may controlthe steering angle, a throttle amount to control the speed of theautonomous vehicle, gear changes, and/or a breaking amount to controlthe extent to which the brakes are engaged. An autonomous vehicle mayoperate in several modes. In some cases, an autonomous vehicle may allowa driver to operate the autonomous vehicle as a conventional vehicle bycontrolling the steering, throttle, clutch, gear shifter, and/or otherdevices. In other cases, a driver may engage the autonomous vehiclenavigation technology to allow the vehicle to be driven by itself.Electrical devices located in an autonomous vehicle can generate heatwhen they perform their respective operations, or such devices can besubjected heat from the sun when the autonomous vehicle is driven on aroad or is parked outdoor.

SUMMARY

This patent document describes systems, apparatus, and methods formanaging temperature of one or more devices operating on or in anautonomous vehicle.

An exemplary system for managing temperature in an autonomous vehiclecomprises one or more computers located in the autonomous vehicle andincluding one or more processors configured to: perform autonomousdriving operations that operate the autonomous vehicle in an autonomousmode; receive one or more messages from a temperature sensor associatedwith an electrical device located on or in the autonomous vehicle whilethe autonomous vehicle is operated in the autonomous mode, where eachmessage includes a temperature value that indicates a temperature atwhich the electrical device is operating; determine a cooling techniqueto reduce the temperature of electrical device, where the coolingtechnique is determined based on a comparison between the temperature ofthe electrical device and a pre-determined threshold value from a set oftwo or more pre-determined threshold values; and perform the coolingtechnique

In some embodiments, the one or more messages are received and thecooling technique is determined by the one or more processors of the oneor more computers being further configured to: receive a first messagethat includes a first temperature value from a temperature sensorassociated with an electrical device located on or in the autonomousvehicle while the autonomous vehicle is operated in the autonomous mode,where the first temperature value indicates the temperature at which theelectrical device is operating; perform a first determination that thefirst temperature value is greater than a first pre-determined thresholdvalue; send, in response to the first determination, a first commandthat instructs a temperature management device associated with theelectrical device to cool the electrical device; the temperaturemanagement device comprising a microcontroller configured to perform thecooling technique comprising: receive the first command; and operate thetemperature management device based on the first command to cool theelectrical device.

In some embodiments, the one or more messages are received and thecooling technique is determined and performed by the one or moreprocessors of the one or more computers being further configured to:receive, after sending the first command, a second message that includesa second temperature value from the temperature sensor associated withthe electrical device; perform a second determination that the secondtemperature value is greater than a second pre-determined thresholdvalue, where the second pre-determined threshold value is higher thanthe first pre-determined threshold value; and perform, in response tothe second determination, an autonomous driving emergency operation.

In some embodiments, the autonomous driving emergency operation isperformed by the one or more processors being configured to disable theautonomous vehicle from being driven in the autonomous mode. In someembodiments, the autonomous driving emergency operation is performed bythe one or more processors being configured to perform drivingoperations that cause the autonomous vehicle to be parked on a side of aroad. In some embodiments, the autonomous driving emergency operationincludes sending a message to be displayed on a monitor associated withthe one or more computers, the message indicates a recommendation todisengage the autonomous mode on the autonomous vehicle, and the messageincludes an identification of the electrical device and a timer thatindicates when the electrical device is expected to reach a knownhighest operating temperature.

In some embodiments, the autonomous driving emergency operation isperformed by the one or more processors being configured to perform ade-rating operation that reduces a computational load or an electricalload on the electrical device. In some embodiments, one or moreprocessors included in the one or more computers is further configuredto: receive, after performing the autonomous driving emergencyoperation, an indication that the autonomous vehicle or the one or morecomputers are instructed to turn off; and send, after receiving theindication, a third command to the temperature management device thatinstructs the temperature management device to cool the electricaldevice for a pre-determined time after the autonomous vehicle or the oneor more computers are turned off. In some embodiments, prior to theperformed autonomous driving operations, the one or more processorsincluded in the one or more computers are further configured to: receivea third message that includes a third temperature value from thetemperature sensor associated with the electrical device; perform adetermination that the third temperature value is greater than apre-defined threshold value; and prevent, in response to thedetermination, the autonomous vehicle from performing the autonomousdriving operations.

In some embodiments, the temperature management device includes a fan, aliquid cooling device, a liquid-to-air cooling device, or anair-conditioning unit. In some embodiments, the first command instructsthe temperature management device to turn on, or increase speed of amotor or pump that circulates air or liquid coolant, or reduce atemperature of air circulated by the temperature management device. Insome embodiments, the electrical device includes a power supply box, anetwork router, an Ethernet switch, an inverter, a backup power supplydevice, or the one or more computers. In some embodiments, the firstmessage and the second message include an identifier associated with theelectrical device.

An exemplary method of managing temperature in an autonomous vehiclecomprises performing autonomous driving operations that operate theautonomous vehicle in an autonomous mode; receiving a first message thatincludes a first temperature value from a temperature sensor associatedwith an electrical device located on or in the autonomous vehicle whilethe autonomous vehicle is operated in the autonomous mode; performing afirst determination that the first temperature value is greater than afirst pre-determined threshold value; sending, in response to the firstdetermination, a first command that instructs a temperature managementdevice associated with the electrical device to cool the electricaldevice; receiving, after sending the first command, a second messagethat includes a second temperature value from the temperature sensorassociated with the electrical device; performing a second determinationthat the second temperature value is greater than a secondpre-determined threshold value, where the second pre-determinedthreshold value is higher than the first pre-determined threshold value;and performing, in response to the second determination, an autonomousdriving emergency operation.

In some embodiments, the autonomous driving emergency operation includesdisabling the autonomous vehicle from being driven in the autonomousmode. In some embodiments, the autonomous driving emergency operationincludes performing driving operations that cause the autonomous vehicleto be parked on a side of the road.

In some embodiments, prior to the performed autonomous drivingoperations, the method comprises: receiving a third message thatincludes a third temperature value from the temperature sensorassociated with the electrical device; performing a determination thatthe third temperature value is greater than a pre-defined thresholdvalue; and preventing, in response to the determination, the autonomousvehicle from performing the autonomous driving operations. In someembodiments, the method further comprises receiving a third message thatincludes a third temperature value from the temperature sensorassociated with the electrical device; performing a determination thatthe third temperature value is greater than a pre-defined thresholdvalue; and preventing, in response to the determination, the autonomousvehicle from performing the autonomous driving operations.

In yet another exemplary aspect, the above-described method is embodiedin a non-transitory computer readable storage medium. The non-transitorycomputer readable storage medium includes code that when executed by aprocessor, causes the processor to perform the methods described in thispatent document.

In yet another exemplary embodiment, a device that is configured oroperable to perform the above-described methods is disclosed.

The above and other aspects and their implementations are described ingreater detail in the drawings, the descriptions, and the claims.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 shows a block diagram of an example vehicle ecosystem in whichtechniques for managing temperature of electrical devices in theautonomous vehicle can be implemented.

FIG. 2A shows an exemplary block diagram of a temperature sensor unitfor a temperature management system.

FIG. 2B shows a block diagram of a cooling device.

FIG. 3 shows an exemplary flow diagram to manage temperature of acritical electrical device in an autonomous vehicle.

FIG. 4 shows another exemplary flow diagram to manage temperature ofelectrical devices on or in an autonomous vehicle.

DETAILED DESCRIPTION

An autonomous vehicle is configured to operate on a road without muchintervention from a human driver. An autonomous vehicle can include acomputer located in the vehicle that can operate the vehicle in anautonomous mode by controlling various system of the vehicle. Forexample, the computer can perform image processing on images obtainedfrom cameras on the vehicle to determine the location of objects thatsurround the vehicle. Based on the image processing, the computer cansafely operate the vehicle by controlling a steering angle of thesteering system, a throttle amount to control the speed of the vehicle,a transmission gear, and/or a braking amount to control the extent towhich the brakes are engaged.

To safely operate the vehicle in an autonomous mode, several sensors aredistributed around the vehicle so that the sensors are coupled todifferent places on the vehicle. Sensors located at different places onthe vehicle enable a computer located in the vehicle to obtain sensordata that describes different regions (e.g., front, rear, side) of anenvironment in which the vehicle is being driven. This patent documentdescribes exemplary techniques to manage the temperature of electricaldevices (e.g., sensors, power supply boxes, Ethernet switch(es)) locatedon or in a vehicle so that these electrical devices can operate within asafe temperature range and can thereby facilitate safe autonomousvehicle operations.

FIG. 1 shows a block diagram of an example vehicle ecosystem 100 inwhich techniques for managing temperature of electrical devices in theautonomous vehicle 105 can be implemented in an in-vehicle controlcomputer 150. The vehicle ecosystem 100 includes several systems andelectrical devices that can generate and/or deliver one or more sourcesof information/data and related services to the in-vehicle controlcomputer 150 that may be located in an autonomous vehicle 105. Examplesof autonomous vehicle 105 include a car, a truck, or a semi-trailertruck. The in-vehicle control computer 150 can be in data communicationwith a plurality of vehicle subsystems 140, all of which can be residentin an autonomous vehicle 105. A vehicle subsystem interface 160 isprovided to facilitate data communication between the in-vehicle controlcomputer 150 and the plurality of vehicle subsystems 140. The vehiclesubsystem interface can include a wireless transceiver, a ControllerArea Network (CAN) transceiver, an Ethernet transceiver, or anycombination thereof.

The autonomous vehicle 105 may include various vehicle subsystems thatsupport of the operation of autonomous vehicle 105. The vehiclesubsystems may include a vehicle drive subsystem 142, a vehicle sensorsubsystem 144, and/or a vehicle control subsystem 146. The vehicle drivesubsystem 142 may include components operable to provide powered motionfor the autonomous vehicle 105. In an example embodiment, the vehicledrive subsystem 142 may include an engine or motor, wheels/tires, atransmission, an electrical subsystem, and a power source.

The vehicle sensor subsystem 144 may include a number of sensorsconfigured to sense information about an environment or condition of theautonomous vehicle 105. For example, the vehicle sensor subsystem 144may include an inertial measurement unit (IMU), a Global PositioningSystem (GPS) transceiver, a RADAR unit, a laser range finder/LIDAR unit,and/or one or more cameras or image capture devices. The vehicle sensorsubsystem 144 may also include sensors configured to monitor internalsystems of the autonomous vehicle 105 (e.g., an 02 monitor, a fuelgauge, an engine oil temperature).

FIG. 2A shows an exemplary block diagram of a temperature sensor unitfor a temperature management system. A temperature sensor unit 200 mayinclude a temperature sensor 205 and a microcontroller 210. Temperaturesensor units 200 may be located on or in several critical autonomousdriving related critical electrical devices (herein referred to as“critical electrical devices”) located in the autonomous vehicle 105.Critical electrical devices can include power supply boxes, powerdistribution units, network routers, Ethernet switches, inverters,backup power supply device (e.g., uninterruptable power supply device),computers with graphic processing unit (GPU) or central processing unit(CPU) to perform image processing on images obtained from cameras on thevehicle such as the in-vehicle control computer described in FIG. 1,etc.,

In the temperature sensor unit 200, the microcontroller 210 can beprogrammable to execute code stored in the microcontroller's memory toenable the microcontroller to instruct a cooling device coupled to orassociated with a critical electrical device to cool the criticalelectrical device if the microcontroller determines that the temperaturevalue measured by the temperature sensor has exceeded a pre-determinedtemperature threshold. The temperature senor unit may include acommunication transceiver 215 so that the microcontroller cancommunicate with and instruct the cooling device (e.g., via a wirelesschannel, a CAN bus, or the Ethernet). A cooling device may be a fan, aliquid cooling pump, a liquid-to-air cooling device, or anair-conditioning unit. In some embodiments, the microcontroller caninstruct the cooling device to turn on or to increase its speed, or todecrease the temperature of the air or liquid circulated by the coolingdevice on the critical electrical device or in an environment thatincludes the critical electrical device. In some embodiments, themicrocontroller in the temperature sensor unit can provide measuredtemperature values of a critical electrical device to the in-vehiclecontrol computer via the transceiver 215.

FIG. 2B shows a block diagram of a cooling device. The cooling devicemay include a motor 255 to operate a fan or to circulate liquid coolant,a microcontroller 260 to execute commands provided to the coolingdevice, and a transceiver to receive the commands from the temperaturesensor unit or the temperate control module of the in-vehicle controlcomputer. In some embodiments, the cooling device can also include atimer 270 that can enable the cooling device to be operated for a lengthof time after the autonomous vehicle has been turned off or shutdown asfurther explained in this patent document.

In FIG. 1, the temperature control module 165 of the in-vehicle controlcomputer 150 can receive temperature values from the temperature sensorunit and can determine whether a measured temperature value exceeds oneor more pre-determined temperature thresholds. As further explained inthis patent document, the temperature control module 165 can instructthe cooling device associated with the critical electrical device tooperate in a manner to cool down the critical electrical device that maybe running hot.

In FIG. 1, the IMU may include any combination of sensors (e.g.,accelerometers and gyroscopes) configured to sense position andorientation changes of the autonomous vehicle 105 based on inertialacceleration. The GPS transceiver may be any sensor configured toestimate a geographic location of the autonomous vehicle 105. For thispurpose, the GPS transceiver may include a receiver/transmitter operableto provide information regarding the position of the autonomous vehicle105 with respect to the Earth. The RADAR unit may represent a systemthat utilizes radio signals to sense objects within the localenvironment of the autonomous vehicle 105. In some embodiments, inaddition to sensing the objects, the RADAR unit may additionally beconfigured to sense the speed and the heading of the objects proximateto the autonomous vehicle 105. The laser range finder or LIDAR unit maybe any sensor configured to sense objects in the environment in whichthe autonomous vehicle 105 is located using lasers. The cameras mayinclude one or more devices configured to capture a plurality of imagesof the environment of the autonomous vehicle 105. The cameras may bestill image cameras or motion video cameras.

The vehicle control subsystem 146 may be configured to control operationof the autonomous vehicle 105 and its components. Accordingly, thevehicle control subsystem 146 may include various elements such as athrottle, a brake unit, a navigation unit, and/or a steering system.

The throttle may be configured to control, for instance, the operatingspeed of the engine and, in turn, control the speed of the autonomousvehicle 105. The brake unit can include any combination of mechanismsconfigured to decelerate the autonomous vehicle 105. The brake unit canuse friction to slow the wheels in a standard manner. The navigationunit may be any system configured to determine a driving path or routefor the autonomous vehicle 105. The navigation unit may additionally beconfigured to update the driving path dynamically while the autonomousvehicle 105 is in operation. In some embodiments, the navigation unitmay be configured to incorporate data from the GPS transceiver and oneor more predetermined maps so as to determine the driving path for theautonomous vehicle 105.

The autonomous control module 168 in the in-vehicle control computer 150may be configured to identify, evaluate, and avoid or otherwisenegotiate potential obstacles in the environment of the autonomousvehicle 105. In general, the autonomous control module 168 may beconfigured to control the autonomous vehicle 105 for operation without adriver or to provide driver assistance in controlling the autonomousvehicle 105. In some embodiments, the autonomous control module 168 maybe configured to incorporate data from the GPS transceiver, the RADAR,the LIDAR, the cameras, and/or other vehicle subsystems to determine thedriving path or trajectory for the autonomous vehicle 105. Theautonomous control module 168 can be activated to enable the vehicle 105to be driven in an autonomous mode. In an example implementation, amonitor or display 172 associated with the in-vehicle control computer150 can show on a graphical user interface (GUI) a prompt to request adriver to indicate whether he or she wants the vehicle 105 to be drivenin autonomous mode. Upon receiving an indication that the driver wantsthe vehicle 105 to be driven in autonomous mode, the autonomous controlmodule 168 can operate the vehicle 105 autonomously. In someembodiments, as further explained in this patent document in FIG. 3, thetemperature control module 165 can send a command to the autonomouscontrol module 168 to disengage autonomous driving operation or todetermine driving path or trajectory to safely park the vehicle 105 onthe side of the road if a critical electrical device is operating at ahazardous temperature.

Many or all of the functions of the autonomous vehicle 105 can becontrolled by the in-vehicle control computer 150. The in-vehiclecontrol computer 150 may include at least one data processor 170 (whichcan include at least one microprocessor) that executes processinginstructions stored in a non-transitory computer readable medium, suchas the data storage device 175 or memory. The in-vehicle controlcomputer 150 may also represent a plurality of computing devices thatmay serve to control individual components or subsystems of theautonomous vehicle 105 in a distributed fashion. In some embodiments,the data storage device 175 may contain processing instructions (e.g.,program logic) executable by the data processor 170 to perform variousmethods and/or functions of the autonomous vehicle 105, including thosedescribed in this patent document. For instance, the data processor 170executes the operations associated with temperature control module 165for managing the temperature of critical electrical devices on or in theautonomous vehicle 105. The data storage device 175 may containadditional instructions as well, including instructions to transmit datato, receive data from, interact with, or control one or more of thevehicle drive subsystem 142, the vehicle sensor subsystem 144, and thevehicle control subsystem 146. In some embodiment, additional componentsor devices can be added to the various subsystems or one or morecomponents or devices (e.g., LiDAR or Radar shown in FIG. 1) can beremoved without affecting the techniques described in this patentdocument for the temperature management system. The in-vehicle controlcomputer 150 can be configured to include a data processor 170 and adata storage device 175.

The in-vehicle control computer 150 may control the function of theautonomous vehicle 105 based on inputs received from various vehiclesubsystems (e.g., the vehicle drive subsystem 142, the vehicle sensorsubsystem 144, and the vehicle control subsystem 146). For example, thein-vehicle control computer 150 may use input from the vehicle controlsubsystem 146 in order to control the steering system to avoid anobstacle detected by the vehicle sensor subsystem 144, move in acontrolled manner, or follow a path or trajectory. In an exampleembodiment, the in-vehicle control computer 150 can be operable toprovide control over many aspects of the autonomous vehicle 105 and itssubsystems.

The example headings for the various sections below are used tofacilitate the understanding of the disclosed subject matter and do notlimit the scope of the claimed subject matter in any way. Accordingly,one or more features of one example section can be combined with one ormore features of another example section.

I. Temperature Management During Autonomous Driving

FIG. 3 shows an exemplary flow diagram to manage temperature of acritical electrical device in an autonomous vehicle. At the receivingoperation 302, the temperature control module of the in-vehicle controlcomputer can receive a first temperature value from a temperature sensorassociated with a critical electrical device located in a vehicle thatis driven in an autonomous mode. In some embodiments, the temperaturesensor unit can send the temperature value with an identifier thatidentifies the critical electrical device whose temperature is beingprovided by the temperature sensor unit. As described in this patentdocument, a vehicle can be driven in an autonomous mode by an in-vehiclecontrol computer that can perform signal/image processing on sensor dataor images provided by cameras to operate various systems (e.g.,steering, brakes, transmission, engine, etc.) of the vehicle withouthuman intervention.

At the determining operation 304, the temperature control module candetermine whether the received temperature is greater than a firstthreshold temperature value. If the received temperature is not greaterthan a first threshold temperature value, then the temperature controlmodule returns to the receiving operation 302 where it can receiveanother temperature value to perform operations described in FIG. 3. Insome embodiments, a temperature sensor unit described in this patentdocument can provide temperature values periodically (e.g., every onesecond, every 2 seconds, every 5 seconds, every ten seconds, etc.).

If the received temperature is greater than a first thresholdtemperature value, then the temperature control module can send acommand to a cooling device associated with the critical electricaldevice to cool down the critical electrical device at the sendingoperation 306. After the sending operation 306, the temperature controlmodule can receive a second temperature value from the temperaturesensor associated with the critical electrical device. The secondtemperature can indicate what effect (if any) the cooling device ishaving on the critical electrical device. For example, if the sendingoperation 306 indicates to a fan associated with the critical electricaldevice to turn on, and if the second temperature value is received atsome time period (e.g., 15 seconds) after the fan is turned on, then thesecond temperature value can indicate whether the fan is successful incooling down the critical electrical device. In another example, if thesending operation 306 indicates to an air-conditioning (AC) unitassociated with a zone in which the critical electrical device islocated to generate cool air at 62 degrees, and if the secondtemperature value is received at some time period (e.g., 10 seconds)after the A/C unit blows cool air, then the second temperature value canindicate whether the fan is successful in cooling down the criticalelectrical device. The receiving operation 308 may be the result of thetemperature sensor unit periodically providing temperature values of thecritical electrical device or the temperature control unit requestingthe microcontroller unit of the temperature sensor unit to provide atemperature value.

At the determining operation 310, the temperature control module candetermine if the second temperature value is greater than a secondthreshold value, where the second threshold value is greater than thefirst threshold value. If the second temperature value is not greaterthan a second threshold value, then the temperature control module canperform the determining operation 304.

There are several technical advantages to having two temperaturethresholds with which the temperature of critical electrical devices inan autonomous vehicle can be managed. One of the technical benefits ofhaving a first and a second temperature threshold, and thedeterminations performed at operations 304 and 310, is to enable thetemperature management system to employ cooling techniques based on ameasured temperature of a critical electrical device. If a measuredtemperature is higher than a first threshold value but less than amaximum temperature value at which the critical electrical device canoperate, then the temperature management system can employ coolingtechniques to cool down the critical electrical device. If a measuredtemperature is higher than a second threshold value which is higher thanthe first threshold value and approaching the maximum temperature valueof the critical electrical device, then the temperature managementsystem can employ a more drastic measure to cool down the criticalelectrical device (e.g., disabling autonomous mode, or initiatingemergency parking sequence to safety stop the vehicle).

At the determining operation 310, if the second temperature value isgreater than a second threshold value, then the temperature controlmodule can determine that the critical electrical device is operating ata temperature that can cause the critical electrical device tomalfunction or stop working, which can be hazardous to autonomousdriving operation. For example, if the critical electrical device is anEthernet router that is used to receive images from cameras located onthe autonomous vehicle and send to the in-vehicle control computer toperform image processing for autonomous driving, and if the Ethernetrouter is operating at a high temperature that causes the Ethernetrouter to shut down or reboot, then such a scenario can be detrimentalfor autonomous driving operation. If the second temperature value isgreater than a second threshold value, then the temperature controlmodule can perform autonomous driving mitigation techniques 312 such assending a command to the autonomous control module to disengage ordisable autonomous mode or to determine driving path or trajectory toperform driving operations to safely park the vehicle on the side of theroad.

At the performing operation 312, the temperature control module can senda message to be displayed on the display associated with the in-vehiclecontrol computer that instructs the driver of an over-temperaturecondition and that autonomous mode is disengaged or that the vehicle isbeing safely driven to park the vehicle on the side of the road. In someembodiments, after the performing operation 312 is executed and thevehicle is either operating in a driver-controlled mode (and not inautonomous mode) or has parked the vehicle on the side of the road, thetemperature control module can send a command to the autonomous controlmodule to prevent autonomous mode to be engaged until the temperature ofthe critical electrical device is determined by the temperature controlmodule to be below the second threshold value. Thus, the temperaturemanagement techniques can enable the critical electrical device to becooled down to a safe temperature range below the second thresholdvalue.

II. Temperature Management Prior to Autonomous Mode Operation

In some scenarios, a vehicle with autonomous driving capability can beparked outdoor or driven and may be subjected to heat from the sun. Insuch scenarios, the critical electrical devices can be exposed toextreme temperatures. When the vehicle is first turned on or at any timeprior to when autonomous mode is engaged, the temperature control modulein the in-vehicle control module can receive a temperature from thetemperature sensor associated with a critical electrical device. If thetemperature control module determines that the temperature of thecritical electrical device is above a pre-defined threshold value (e.g.,the second threshold value as explained in FIG. 3), then the temperaturecontrol module can send a command to the autonomous control module toprevent autonomous mode to be engaged until the temperature of thecritical electrical device is determined by the temperature controlmodule to be below the threshold value. In some embodiments, when adriver indicates via a GUI associated with display of the in-vehiclecontrol computer that he or she wants to engage autonomous modeoperation, the temperature control module can compare temperature valuesof the critical electrical devices to their respective threshold valuesto determine whether autonomous mode should be allowed.

III. Temperature Management to Advise Shutdown or De-Rated Operation

In some scenarios, when a vehicle is being operated in an autonomousmode and one of the critical electrical devices is operating at atemperature deemed to be high enough to be unsafe for autonomousdriving, such as described in operations 310 and 312 of FIG. 3, thetemperature control module can perform additional or alternativeoperations at the performing operation 312.

In some embodiments, the temperature control module can advise ashutdown of the autonomous mode or of the vehicle if the temperaturecontrol module can, based on the rate at which the temperature of thecritical electrical device is increasing, calculates that the criticalelectrical device may reach its previously known highest operatingtemperature within a pre-determined time window (e.g., within the next10 minutes or next 1 minute or next 2 minute from when the temperaturecontrol module calculates that the critical electrical device will reachits previously known highest operating temperature). For example, thetemperature values received at operations 302 and 308 can be associatedwith a timestamp with which the temperature control module can determinea rate at which the temperature of the critical electrical device may beincreasing. Since the highest operating temperature of the criticalelectrical device may be previously known by the temperature controlmodule (e.g., the highest operating temperature may be provided by amanufacturer of a device), the temperature control module can calculatethe time when the critical electrical device would be expected to reachand operate at its highest operating temperature.

If the calculated time is within a pre-determined window (e.g., 10minutes), then the temperature control module can send a message to thedisplay associated with the in-vehicle control computer to show amessage to the driver that recommends that autonomous mode isrecommended to be disengaged by the driver due to excessive temperatureof the critical electrical device. In some embodiments, the message maybe shown with an identification of the critical electrical device thatis experiencing excessive heat and a timer that can count down from thetime calculated by the temperature control module when the criticalelectrical device is expected to reach its highest operatingtemperature. The displayed message may also include a button thatenables the driver to disengage autonomous mode. Upon receiving anindication that the driver wants the vehicle to be disengaged fromautonomous mode, the autonomous control module can cease autonomousdriving operation and allow the driver to control the vehicle.

In some embodiments, the temperature control module can de-rateoperations of the in-vehicle control computer or other criticalelectrical device(s) if the temperature control module can, based on therate at which the temperature of the critical electrical device isincreasing, calculates that the critical electrical device may reach itspreviously known highest operating temperature within a pre-determinedtime window (e.g., within the next 10 minutes). A de-rated operation caninclude the temperature control module sending a command to thein-vehicle control computer to disable parallel or redundant processingperformed by the in-vehicle control computer. In other examples, ade-rated operation can include instructing the camera to provide imagesat a lower image frame rate (e.g., 12 frames per second (fps) as opposedto 60 fps) or instructing the in-vehicle control computer to performimage processing on every n-th image frame provided by the camerainstead of on every image frame (e.g., on every fifth image frameprovided by the cameras).

IV. Temperature Management after Vehicle is Powered Down

In some embodiments, when the driver initiates the process to power downthe vehicle (e.g., indicates via the display of the in-vehicle controlcomputer to safely shutdown the system), the temperature control modulecan send a command to a timer associated with a cooling device (shown as270 in FIG. 2B) to enable the cooling device to continue to cool thecritical electrical device(s) that are determined to operate above athreshold value (e.g., the second threshold value as explained in FIG.3) for a length of time after the vehicle has been turned off or shutdown. In some embodiments, the command sent by the temperature controlmodule to the microcontroller of the temperature sensor unit canindicate an amount of time that that the cooling device is expected tooperate. For example, when the in-vehicle control computer or theautonomous vehicle is instructed to shut down, the temperature controlmodule can instruct the timer of the cooling device to continue tooperate for a pre-determined length of time (e.g., 2 minutes) tocontinue to cool down critical electrical device associated with thecooling device. In some embodiments, the temperature control module canenter after-run mode after the in-vehicle control computer is instructedto shut down, where the temperature control module in the after-run modecan, for example, interrupt the shutdown and can continue to monitor thetemperature and instruct the cooling device to continue to cool thedevices until the devices reach a pre-determined temperature (e.g.,ambient temperature).

In some embodiments, the temperature control module can control thecooling device to minimize humidity or condensation. For example, atemperature control module can send a commend to an air-conditioningunit to turn on to dehumidify or to minimize condensation the area wherethe critical electrical device is located.

FIG. 4 shows another exemplary flow diagram to manage temperature ofelectrical devices on or in an autonomous vehicle. In some embodiments,one or more computers located in the autonomous vehicle, where eachcomputer includes a processor that is configured to perform operations402 to 414. At the performing operation 402, performing autonomousdriving operations that operate the autonomous vehicle in an autonomousmode. At the receiving operation 404, receiving a first message thatincludes a first temperature value from a temperature sensor associatedwith an electrical device located on or in the autonomous vehicle whilethe autonomous vehicle is operated in the autonomous mode.

At the performing operation 406, performing a first determination thatthe first temperature value is greater than a first pre-determinedthreshold value. At the sending operation 408, sending, in response tothe first determination, a first command that instructs a temperaturemanagement device associated with the electrical device to cool theelectrical device. At the receiving operation 410, receiving, aftersending the first command, a second message that includes a secondtemperature value from the temperature sensor associated with theelectrical device.

At the performing operation 412, performing a second determination thatthe second temperature value is greater than a second pre-determinedthreshold value, where the second pre-determined threshold value ishigher than the first pre-determined threshold value. At the performingoperation 414, performing, in response to the second determination, anautonomous driving emergency operation.

In some embodiments, the autonomous driving emergency operation includesdisabling the autonomous vehicle from being driven in the autonomousmode. In some embodiments, the autonomous driving emergency operationincludes performing driving operations that cause the autonomous vehicleto be parked on a side of the road. In some embodiments, the autonomousdriving emergency operation includes sending a message to be displayedon a monitor associated with one or more computers located in theautonomous vehicle, where the message indicates a recommendation todisengage the autonomous mode on the autonomous vehicle, and where themessage includes an identification of the electrical device and a timerthat indicates when the electrical device is expected to reach a knownhighest operating temperature. In some embodiments, the autonomousdriving emergency operation is performed by the one or more processorsbeing configured to perform a de-rating operation that reduces acomputational load or an electrical load on the electrical device.

In some embodiments, the method of FIG. 4 further comprises receiving,after performing the autonomous driving emergency operation, anindication that the autonomous vehicle or one or more computers locatedin the autonomous vehicle are instructed to turn off, and sending, afterreceiving the indication, a third command to the temperature managementdevice that instructs the temperature management device to cool theelectrical device for a pre-determined time after the autonomous vehicleor the one or more computers are turned off

In some embodiments, prior to the performed autonomous drivingoperations, the method shown in FIG. 4 further comprises: receiving athird message that includes a third temperature value from thetemperature sensor associated with the electrical device; performing adetermination that the third temperature value is greater than apre-defined threshold value; preventing, and in response to thedetermination, the autonomous vehicle from performing the autonomousdriving operations. In some embodiments, the temperature managementdevice includes a fan, a liquid cooling device, a liquid-to-air coolingdevice, or an air-conditioning unit.

In some embodiments, the first command instructs the temperaturemanagement device to turn on, or increase speed of a motor or pump thatcirculates air or liquid coolant, or reduce a temperature of aircirculated by the temperature management device. In some embodiments,the electrical device includes a power supply box, a network router, anEthernet switch, an inverter, a backup power supply device, or one ormore computers. In some embodiments, the first message and the secondmessage include an identifier associated with the electrical device.

In this document the term “exemplary” is used to mean “an example of”and, unless otherwise stated, does not imply an ideal or a preferredembodiment. In this document, the term “microcontroller” can include aprocessor and its associated memory.

Some of the embodiments described herein are described in the generalcontext of methods or processes, which may be implemented in oneembodiment by a computer program product, embodied in acomputer-readable medium, including computer-executable instructions,such as program code, executed by computers in networked environments. Acomputer-readable medium may include removable and non-removable storagedevices including, but not limited to, Read Only Memory (ROM), RandomAccess Memory (RAM), compact discs (CDs), digital versatile discs (DVD),etc. Therefore, the computer-readable media can include a non-transitorystorage media. Generally, program modules may include routines,programs, objects, components, data structures, etc. that performparticular tasks or implement particular abstract data types. Computer-or processor-executable instructions, associated data structures, andprogram modules represent examples of program code for executing stepsof the methods disclosed herein. The particular sequence of suchexecutable instructions or associated data structures representsexamples of corresponding acts for implementing the functions describedin such steps or processes.

Some of the disclosed embodiments can be implemented as devices ormodules using hardware circuits, software, or combinations thereof. Forexample, a hardware circuit implementation can include discrete analogand/or digital components that are, for example, integrated as part of aprinted circuit board. Alternatively, or additionally, the disclosedcomponents or modules can be implemented as an Application SpecificIntegrated Circuit (ASIC) and/or as a Field Programmable Gate Array(FPGA) device. Some implementations may additionally or alternativelyinclude a digital signal processor (DSP) that is a specializedmicroprocessor with an architecture optimized for the operational needsof digital signal processing associated with the disclosedfunctionalities of this application. Similarly, the various componentsor sub-components within each module may be implemented in software,hardware or firmware. The connectivity between the modules and/orcomponents within the modules may be provided using any one of theconnectivity methods and media that is known in the art, including, butnot limited to, communications over the Internet, wired, or wirelessnetworks using the appropriate protocols.

While this document contains many specifics, these should not beconstrued as limitations on the scope of an invention that is claimed orof what may be claimed, but rather as descriptions of features specificto particular embodiments. Certain features that are described in thisdocument in the context of separate embodiments can also be implementedin combination in a single embodiment. Conversely, various features thatare described in the context of a single embodiment can also beimplemented in multiple embodiments separately or in any suitablesub-combination. Moreover, although features may be described above asacting in certain combinations and even initially claimed as such, oneor more features from a claimed combination can in some cases be excisedfrom the combination, and the claimed combination may be directed to asub-combination or a variation of a sub-combination. Similarly, whileoperations are depicted in the drawings in a particular order, thisshould not be understood as requiring that such operations be performedin the particular order shown or in sequential order, or that allillustrated operations be performed, to achieve desirable results.

Only a few implementations and examples are described and otherimplementations, enhancements and variations can be made based on whatis described and illustrated in this disclosure.

What is claimed is:
 1. A system for managing temperature in an autonomous vehicle, comprising: one or more computers located in the autonomous vehicle and including one or more processors configured to: perform autonomous driving operations that operate the autonomous vehicle in an autonomous mode; receive one or more messages from a temperature sensor associated with an electrical device located on or in the autonomous vehicle while the autonomous vehicle is operated in the autonomous mode, wherein each message includes a temperature value that indicates a temperature at which the electrical device is operating; determine a cooling technique to reduce the temperature of electrical device, wherein the cooling technique is determined based on a comparison between the temperature of the electrical device and a pre-determined threshold value from a set of two or more pre-determined threshold values; and perform the cooling technique.
 2. The system of claim 1, wherein the one or more messages are received and the cooling technique is determined by the one or more processors of the one or more computers being further configured to: receive a first message that includes a first temperature value from a temperature sensor associated with an electrical device located on or in the autonomous vehicle while the autonomous vehicle is operated in the autonomous mode, wherein the first temperature value indicates the temperature at which the electrical device is operating; perform a first determination that the first temperature value is greater than a first pre-determined threshold value; send, in response to the first determination, a first command that instructs a temperature management device associated with the electrical device to cool the electrical device; the temperature management device comprising a microcontroller configured to perform the cooling technique comprising: receive the first command; and operate the temperature management device based on the first command to cool the electrical device.
 3. The system of claim 2, wherein the one or more messages are received and the cooling technique is determined and performed by the one or more processors of the one or more computers being further configured to: receive, after sending the first command, a second message that includes a second temperature value from the temperature sensor associated with the electrical device; perform a second determination that the second temperature value is greater than a second pre-determined threshold value, wherein the second pre-determined threshold value is higher than the first pre-determined threshold value; and perform, in response to the second determination, an autonomous driving emergency operation.
 4. The system of claim 3, wherein the autonomous driving emergency operation is performed by the one or more processors being configured to disable the autonomous vehicle from being driven in the autonomous mode.
 5. The system of claim 3, wherein the autonomous driving emergency operation includes sending a message to be displayed on a monitor associated with the one or more computers, wherein the message indicates a recommendation to disengage the autonomous mode on the autonomous vehicle, and wherein the message includes an identification of the electrical device and a timer that indicates when the electrical device is expected to reach a known highest operating temperature.
 6. The system of claim 3, wherein the autonomous driving emergency operation is performed by the one or more processors being configured to perform a de-rating operation that reduces a computational load or an electrical load on the electrical device.
 7. The system of claim 3, wherein one or more processors included in the one or more computers is further configured to: receive, after performing the autonomous driving emergency operation, an indication that the autonomous vehicle or the one or more computers are instructed to turn off; and send, after receiving the indication, a third command to the temperature management device that instructs the temperature management device to cool the electrical device for a pre-determined time after the autonomous vehicle or the one or more computers are turned off.
 8. The system of claim 3, wherein prior to the performed autonomous driving operations, the one or more processors included in the one or more computers are further configured to: receive a third message that includes a third temperature value from the temperature sensor associated with the electrical device; perform a determination that the third temperature value is greater than a pre-defined threshold value; and prevent, in response to the determination, the autonomous vehicle from performing the autonomous driving operations.
 9. The system of claim 8, wherein the pre-defined threshold value is the second pre-determined threshold value.
 10. The system of claim 1, wherein the electrical device includes a power supply box, an inverter, or a backup power supply device.
 11. The system of claim 2, wherein the temperature management device includes a fan, a liquid cooling device, or a liquid-to-air cooling device.
 12. The system of claim 2, wherein the first command instructs the temperature management device to turn on, or increase speed of a motor or pump that circulates air or liquid coolant.
 13. The system of claim 3, wherein the first message and the second message include an identifier associated with the electrical device.
 14. A method of managing temperature in an autonomous vehicle, comprising: performing autonomous driving operations that operate the autonomous vehicle in an autonomous mode; receiving a first message that includes a first temperature value from a temperature sensor associated with an electrical device located on or in the autonomous vehicle while the autonomous vehicle is operated in the autonomous mode; performing a first determination that the first temperature value is greater than a first pre-determined threshold value; sending, in response to the first determination, a first command that instructs a temperature management device associated with the electrical device to cool the electrical device; receiving, after sending the first command, a second message that includes a second temperature value from the temperature sensor associated with the electrical device; performing a second determination that the second temperature value is greater than a second pre-determined threshold value, wherein the second pre-determined threshold value is higher than the first pre-determined threshold value; and performing, in response to the second determination, an autonomous driving emergency operation.
 15. The method of claim 14, wherein the autonomous driving emergency operation includes performing driving operations that cause the autonomous vehicle to be parked on a side of a road.
 16. The method of claim 14, further comprising: receiving a third message that includes a third temperature value from the temperature sensor associated with the electrical device; performing a determination that the third temperature value is greater than a pre-defined threshold value; and preventing, in response to the determination, the autonomous vehicle from performing the autonomous driving operations.
 17. The method of claim 14, wherein the temperature management device includes an air-conditioning unit.
 18. The method of claim 14, wherein the first command instructs the temperature management device to reduce a temperature of air circulated by the temperature management device.
 19. The method of claim 14, wherein the electrical device includes a network router, an Ethernet switch, or one or more computers.
 20. A non-transitory computer readable storage medium having code stored thereon, the code, when executed by a processor, causing the processor to implement a method of managing temperature in an autonomous vehicle, comprising: performing autonomous driving operations that operate the autonomous vehicle in an autonomous mode; receiving a first message that includes a first temperature value from a temperature sensor associated with an electrical device located on or in the autonomous vehicle while the autonomous vehicle is operated in the autonomous mode; performing a first determination that the first temperature value is greater than a first pre-determined threshold value; sending, in response to the first determination, a first command that instructs a temperature management device associated with the electrical device to cool the electrical device; receiving, after sending the first command, a second message that includes a second temperature value from the temperature sensor associated with the electrical device; performing a second determination that the second temperature value is greater than a second pre-determined threshold value, wherein the second pre-determined threshold value is higher than the first pre-determined threshold value; and performing, in response to the second determination, an autonomous driving emergency operation. 